Joints between structural members

ABSTRACT

A joint between structural members such as edge members of panelled furniture, the joint being secured by a bracket having leaves which each abut and are secured to one of the structural members. The leaves each have an axis and the axes intersect to define a plane, the faces of the leaves abutting the structural members being obliquely inclined to that plane.

llnited States Patent Inventor Hendrik Pieter Zwennls Y 50 MurrayAvenue, Meredale,

Johannesburg, Republic of South Africa Appl. No. 780,523

Filed Dec. 2, 1968 Patented Aug. 24, 1971 Priority Dec. 13, 1967 SouthAfrica 67/7489 JOINTS BETWEEN STRUCTURAL MEMBERS 1 Claim, 1 DrawingFigs.

U.S. Cl

Int. Cl. F 16b 7/00 Field of Search 287/] 89.36 H, 20.92 D, 54 B [56]References Cited UNITED STATES PATENTS 471,610 3/1892 Hart 287/2092 D2,371,493 3/1945 Asehinger. 287/2092 D 2,904,360 9/1959 Gamlen 287/54 B3,144,265 8/1964 Humble 287/54 B FOREIGN PATENTS 371,570 10/1963Switzerland 287/18936 l-l Primary Examiner-David .l. WilliamowskyAssistant Examiner-Andrew V. Kundrat Attorney-Young & Thompson ABSTRACT:A joint between structural members such as edge members of panelledfurniture, the joint being secured by a bracket having leaves which eachabut and are secured to one of the structural members. The leaves eachhave an axis and the axes intersect to define a plane, the faces of theleaves abutting the structural members being obliquely inclined to thatplane.

JOINTS BETWEEN STRUCTURAL MEMBERS This invention relates to jointsbetween structural members such as framework members of articles offurniture, and particularly to joints between two or three mutuallyperpendicular members.

The jointing of structural members of this type, whether of metal ortimber, is traditionally a task calling for a skilled craftsman. In anage when craftsmen are becoming scarce and do-it-yourself" systems havean enormous following, much attention has been paid to thesimplification of traditional joints. Several systems have emerged inrecent times to enable the amateur joiner or cabinetmaker or metalworkerto make technically sound jointed articles with the minimum of training,skill, labor and equipment. As far as the applicant is aware, however,no fully satisfactory proposal has yet been made forthe simplifiedjointing of structural members that are intended to support the edges ofpanels.

An object of this invention is to provide a novel simplified jointingsystem for angularly inclined structural members, whether of metal,timber, plastics or other material, and a novel bracket for use in thejoint. The system is particularly suitable for joints betweenpanel-supporting members, although it is also useful in other contexts.

According to one aspect of the invention, a bracket for use in a jointbetween two juxtaposed angularly inclined structural members comprisestwo angularly inclined leaves, each leaf having an axis and a faceadapted to abut a surface of one of the structural members, the axes ofthe leaves intersecting to define a plane and the faces of the leaveseach having a generally oblique inclination to that plane; and means connecting the leaves to hold them in position relatively to each other.

The bracket may also include means for attaching the leaves to thestructural members.

Another aspect of the invention provides a jointed structure comprisinga plurality of juxtaposed angularly inclined structural members, thejoint between the members being secured by a bracket as described abovewith a face of each leaf of the bracket abutting and being secured to asurface of a structural member.

The structural members preferably have surfaces complemental to the leaffaces, and formations to inhibit movement of the bracket leaves out ofposition.

In a preferred form, the faces of the bracket leaves are flat and areeach inclined at substantially 45 to the plane defined by the axes ofthe leaves. Where the structural members are to be joined at rightangles to each other, the leaf faces are mutually perpendicular. Theleaves are elongated, and are pierced to accommodate screws or the likefor attachment to the structural members. The bracket is formed ofpressed steel plate or some other stiff material. The leaves do notconverge to a point, being connected by an expanse of the plate inclinedto each of the leaves and extending across the included angle betweentheir axes.

For use in a joint between three structural members, the bracketincludes a third leaf corresponding to the other leaves, for secural toa surface of the third structural member. Where the joint encompassesthree mutually perpendicular members, the leaf axes will also bemutually perpendicular. Various embodiments of the invention aredescribed below with reference to the accompanying drawings, in which:

FIG. I is an isometric view ofa two-leaf bracket for use in a jointbetween two mutually perpendicular structural members;

FIG. 2 is an isometric view of the bracket of FIG. 1 in place in acompleted joint between two edge members of a type suitable for use inpanelled furniture;

FIG. 3 is an isometric view of a three-leaf bracket for use in a jointbetween three mutually perpendicular structural members;

FIG. 4 is a sectional view through a preferred form of structural memberto which one leaf of the bracket of FIG. 3 has been attached;

FIG. 5 is an isometric view of a completed joint incorporating thebracket of FIGS. 3 and 4, the joint forming a corner of a framework fora panelled article of furniture;

FIG. 6 is a perspective view from above of the joint of FIG. 5; and

FIG. 7 is an isometric view of another joint using the threeleaf bracketof FIGS. 3 and 4, the joint forming a corner of a framework of anarticle of furniture incorporating a shelf.

A preferred form of bracket is shown in FIG. I. It is designed for usebetween two mutually perpendicular structural members, and is formed bycutting and pressing from steel plate of suitable thickness to make thefinished joint rigid. The bracket, indicated generally at 10, comprisestwo identical leaves 12, 12, connected by a bridge portion 14. Theleaves are of constant cross section except at their rounded ends, andhave axes l6, 16, shown in dotted lines, that intersect to define aplane. The leaves are so formed that their flat surfaces are eachinclined at an angle of 45 to the plane defined by the axes 16, 16. Atthe same time, the corresponding flat surfaces of the two leaves aremutually perpendicular. Thus the flat surfaces seen at l8, 18, in FIG. 1are mutually perpendicular.

Each leaf is bored at 20 to provide holes for securing bolts or screwsor the like.

FIG. 2 shows the bracket 10 of FIG. I installed in a T-joint between avertical structural member 22 and a horizontal member 24. The members22, 24 are in this instance wooden laths shaped by spindling or the liketo the required section. In the drawing, the joint is intended toaccommodate panels above and below the member 24, and grooves 26, 28 and30 are provided to receive the edges of these panels and hold themsecurely.

Each of the members 22, 24 is provided with a surface against which theoperative face of a leaf 12 is adapted to abut. On the member 22, thissurface is shown as the 45 bevel 32. On the horizontal member 24 thesurface is shown as the bevel 34. Each of the surfaces has a grooverunning centrally along its length to facilitate location of the bracket10, the groove being shown at 36 on the surface 32, and at 38 on thesurface 34.

Screws 40 extend through the holes 20 (invisible in FIG. 2) into themembers 22 and 24 to hold the bracket 10 in place.

The bridge portion 14 of the bracket 10 eliminates a sharp cornerbetween the leaves 12, 12, spanning the included angle between them.This blunting, as it were, of the bracket apex or corner simplifiesmanufacture of the bracket and also prevents cluttering of the space inthe shoulder of the joint, where any slight inaccuracy in the bracketsurface on the structural members might otherwise leave unsightly andundesirable gaps.

In practice, the joint shown in FIG. 2 might exist in any of manyarticles of panelled domestic or other furniture, or even in cabinets orshelving or other fitting for shops, warehouses, laboratories, and soon.

Where three mutually perpendicular members are to be connected in ajoint, a three-leaved bracket of the kind shown in FIG. 3 is preferred.The bracket 40 of FIG. 3 is in effect a development of the bracket 10 ofFIG. 1, having three identical and symmetrically arranged leaves, 42,42, 42 similar to the leaves 12 in FIG. 1. A bridge portion 44 connectsthe leaves 42 together, again eliminating a sharp apex or corner.

In practice the plane of the bridge 44 is inclined at an angle ofapproximately 54 to the planes of the surfaces of each of the leaves 42,this angle conferring the required symmetry and locating the leavesproperly for a joint of three mutually perpendicular structural members.

FIG. 4 shown the bracket 40 of FIG. 3 connected to a preferred form ofstructural member according to the invention, this member being anextruded section of aluminum or the like shown at 46. The section 46 isdesigned particularly as a edge member for panelled furniture, and hasgrooves 48, 50 to receive the edges of panels (not illustrated). Theedge of the member 46 between the grooves 48, 50 is cut away to define agroove to receive one of the leaves of the bracket 40.

The floor 52 of this groove is formed with an undercut cavity 54 whichreceives the shanks of bolts 58 and square nuts 56 engagirig the boltshanks, the bolts 58 serving to hold the bracket 40 rigidly in place onthe member 46.

Transverse movement of the leaf 12 is prevented independently of thebolts 58 by shoulders 60 on the member 46 flanking the groove floor 52.The bracket is initially brought into place by screwing the nuts 56 onto the ends of the shanks of the bolts 58, and sliding leaf l2longitudinally along the groove with the nuts in the undercut cavity 54,and tightening up the bolts only when it is correctly located. The nuts56 are of a size to be held against rotation in cavity 54. The bridge 44is so shaped and inclined that the bracket is freely slidable along thegroove of the member 46, and in the completed joint, clears theshoulders 60 adequately.

FIG. shows a bracket 40 in place in a joint between three structuralmembers 46 forming the corner of a framework for a panelled article offurniture or the like. Each leaf is held with its outer flat faceabutting the groove floor surface 52 and shoulders 60 ofa member 46,with bolts 58 locking the assembled joint rigidly together. The bridgeportion 44 covers the apex of thejoint.

FIG. 6 shown a view from above of the joint of FIG. 5. To form itneatly, it is preferred to cut two of the members 46, in practice thosethat extend horizontally in the finished article, at a 45 angle, thejunction of these members being shown by the line 64. The verticalmember 46 is cut square, to abut square-on against the other members 46.With accurate cutting and assembly, the joint lines are barelynoticeable in the finished framework.

A different application of the bracket 40 of FIGS. 3 to 6 is shown inFIG. 7. Here there is a sturdy vertical structural member 70, such asmight form a floor-to-ceiling post for built-in wall furniture. A groove71 is provided in the member 70 to receive panels (not illustrated). Twohorizontal members 72 and 74, of differing section, are joined to themember 70. The member 74 has three panel-receiving grooves 76, 78 and80, while the member 72 has a single panel-receiving groove 82.

Each of the members 70, 72 and 74, which are conveniently extrudedaluminum sections, has a cutaway corner formed with a groove floor 52and shoulders 60, as described in relation to the members 46 of FIGS. 4to 6. The joint between these members is supported by a three-leavedbracket 40 of the king shown in FIGS. 3 to 6, and bolts 58 engaging nuts(not visible) in the cavities 54 of the members. As illustrated, thejoint is suitable for the framework of an article of furniture or shopfitting or the like in which a horizontal shelf or panel is requiredbetween the members 72 and 74, and vertical panels between the members70 and 74, both above and below the level of the member 74. These panelsare not illustrated, but

would be held in the grooves of the structural members, being wedged inthe grooves if necessary.

Where it is undesirable to have exposed bevelled surfaces, such as thegrooved cutaway comer of the member 46 in FIGS. 4 to 6, a closure stripcan be unobtrusively secured to the member to cover the surface.

While structural members that are elongated and of uniform cross sectionhave been described and illustrated, they need not be so; they mayindeed be members of bulky or blocky shape. Nor need they be of wood ormetal, as other materials such as hard plastics are suitable.

With certain structural members, instead of securing the brackets byscrews or bolts, spikes or like protrusions might be provided to beimpressed into the body of the structural members; or self-tappingscrews might be used. Other connection means are also feasible.

One of the main advantages of the system described above is that thejoint can be made solely along surfaces of the structural members suchas bevels, leaving the adjoining surfaces unencumbered. Where panels areused, these adjoining surfaces can be grooved or rebated withoutinterference from the bracket, allowing neatness in the finished joint.

Another advantage IS the simplicity of assembly. With structural membersand brackets as described in this specification, only a screwdriver isneeded to assemble what may be a complex piece of furniture or shopfitting or the like; provided, of course, that the structural elementshave been cut to the cor rect dimensions. Costly and elaborate jointingtools, and even glue, are totally eliminated. Ease of dismantling, ofcourse, matches ease of assembly.

Another advantage is the rigidity of the joint, which results not fromdirect interengagement of the structural members but from the rigidityof the bracket connecting them. The joint remains rigid even if thereare inaccuracies in the dimensions of the structural members.

I claim:

1. The combination of a plurality of elongated members and a bracketconnecting the members so that they lie at inclined positions, thebracket having a plurality of mutually inclined leaves which are stoppedshort of the point of intersection and a bridge which spans the includedangle between them, the leaves having openings therein and the leavesand the bridge lying in a space bounded by the outer surfaces of theleaves, each member comprising a front part and reentrant means behindthe front part, the reentrant means having an outwardly directed surfaceagainst which a leaf lies, a space located below the surface and apassage passing from the space to the surface, the combination furthercomprising, for each leaf, clamping means passing through the leafopenings and the passage in the associated member and having head meanslocated respectively within the space and above the leaf.

1. The combination of a plurality of elongated members and a bracketconnecting the members so that they lie at inclined positions, thebracket having a plurality of mutually inclined leaves which are stoppedshort of the point of intersection and a bridge which spans the includedangle between them, the leaves having openings therein and the leavesand the bridge lying in a space bounded by the outer surfaces of theleaves, each member comprising a front part and reentrant means behindthe front part, the reentrant means having an outwardly directed surfaceagainst which a leaf lies, a space located below the surface and apassage passing from the space to the surface, the combination furthercomprising, for each leaf, clamping means passing through the leafopenings and the passage in the associated member and having head meanslocated respectively within the space and above the leaf.